Kiln for decorated ceramic ware



KILN FOR DECORATED CERAMIC WARE May 1 Y E M R O T T A INVENTOR.

3 Sheets-Sheet l T o AW ER/M m m Y Filed Feb. 28, 1950 L. L. RCDCJT KILN FOR DECORAT May 1 1% ED CERAMIC WARE 5 Sheecs-Sheat 5 Filed Feb. 28, 1950 NLW ATTORNEY Patented May 1, 1951 UNITED STATES t ATENT OFFICE Claims.

This invention relates to kilns, but particularly to a kiln for decorated ceramic ware, and an object is to produce a simple and eificient kiln of this character which is so constructed and designed as to enable ceramic objects such, for eX-- ample, as decorated ceramic ware to be advanced or progressed through the kiln so that at the discharge end, the ware is ready to be packaged.

.Another object is to produce a kiln embodying an open ended mufile chamber through which the ceramic ware is passed, new and improved heating. means within the mufiie chamber enabling preheating, firing and cooling of the ware as it progresses through the mufiie. chamber.

.A furtherobject is. to produce an open ended kiln for decorated ceramic ware having articulated supporting elements for the ware which are progressively advanced through the kiln by driven elements which provide the hearth of the U kiln. o

A fufther object is to produce a kiln, the hearth of which .constitutesthe propelling means foradvancing the objects through the kiln, the support for the ceramic ware being in the form of an end less articulated device, means being provided exteriorly of the kiln to enable ware to be conveniently. mounted on the endless device for passage through the kiln and to enable such ware which has passed through the kiln to be removed forpackaging, thereby reducing the amount of handling of the ware and enabling the work of handlingto be performed by a minimum number of operators.

Ajstill further object is to provide an endless kiln or mufile chamber with new and improved heating means by means of radiant tubes so arranged that the heat is efiiciently employed and firing of the ceramic ware.

throughout the muflie chamber for preheating A still further object is to produce a new and improved apparatus for decorated ceramic'ware having an open ended mufile chamber, the hearth of which constitutes driven elements onwhich an'endless series of articulated supporting panels rest and are propelled thereby and having on the outside of the muffle chamber supporting means tration but not of limitation, an embodiment of the invention is shown on the accompanying drawings, in which Figure 1 is a top plan view somewhat diagrammatic and with parts broken away for purposes of clarity showing an apparatus for decorated ceramic ware including an elongate open ended kiln and showing driven rollers forming the hearth of the kiln and idlers, and showing the articulated supporting plates or bats by which the ceramic ware is carried to and from the kiln;

Figure 2 is a fragmentary side elevation of a .portion of the kiln shown in Figure 1, some parts being omitted and showing particularly the arrangement of the radiant heating tubes for the muflie chamber;

Figure 3 is a vertical sectional elevation on an enlarged scale taken substantially on the line 3-3 of Figure 2, showing somewhat diagrammatically the preheating end of the muffle chamtially on the line '44 of Figure 2 and on an enlarged scale and showing the interior of the mufile chamber in the firing region; and

Figure 5 is a perspective view of the heating tube arrangement by which the preheating and firing zones for the kiln are produced.

The illustrated embodiment of the invention comprises an elongate open ended kiln Ill providing a passage therethrough, through which the decorated ware is advanced. As shown in Figure 3, the opposite end portions of the kiln have side walls made up of tiers of brick II and I3 with interposed insulation I2 of any suitable character. The inverted Y-shaped flue I4 of sheet metal connects at its lower end with flues l5 and 15 which extend longitudinally of the kiln and are made up of a series of tile extending for a short portion of the length of the kiln. The mufile chamber is formed with a bottom wall ll, side walls l8 and top wall !9 suitably joined together, these walls being preferably of fire brick. The preheating zone of the kiln is relatively narrow as indicated in Figure 3, whereas the firing zone disposed substantially centrally of the kiln is enlarged as indicated in Figure 4, in which the vertical side walls 20 and base 2! are of fire brick, a chrome nickle transverse beam 22 supporting a fire brick ceiling 23 above which is mounted suitable insulation 24. 'Iflie firing zone of the 3 kiln is enlarged to accommodate the tubes which radiate the heat. The arrangement of the tubes is important in delivering the maximum heat in the firing zone and a reduced heat for the preheating zone.

As shown, on one side of the muflie chamber is a pair of vertically disposed parallel tubes and 26 and on the opposite side is a pair of similarly arranged tubes 21 and 28. The tubes 25 and 26 extend to the flue l5 and the tubes 27 and 28 extend to the tube or flue l6 delivering to these tubes the gases or products of combustion which are drawn up through the Y-shaped exhaust pipe [4 and through a pipe 29 by an exhaust fan 30 for discharging to the outside, it being understood that the fan may be driven in any suitable manner as by an electric motor 3|.

Leading to the horizontally extending tube 25 is a plurality of laterally spaced parallel tubes, each of which has a downwardly extending portion 32 and a transverse portion 33 which extends across the lower portion of the firing zone of the mufile chamber and spaced from adjacent walls so that full advantage of the radiant heat may be had. The end portion of each transverse tube portion 33 extends through an opening 34 in the adjacent side wall of the muiile chamber and has an open end to receive a burner 35 employing gas or oil as fuel, which, as will be readily understood by those skilled in the art, projects its flame well into the transverse tube portion 33 to create the desired radiant heat. The horizontal tube 21 has a plurality of laterally spaced tubes alternating with the tubes 33 and each of these tubes has a downwardly extending portion 35, a transverse portion 31 in parallel relation to the tube portions 33, the end portions of the transverse tube portions 31 extending through the opposite wall of the muffle chamber to receive burners 35 as above described.

Leading to the horizontal tube 26 is a plurality of tubes having upwardly extending portions 33 and transverse portions 39 which'are in laterally spaced parallel relation to each other and extend through the opposite wall of the mufile chamber to receive a similar burner 35. From the horizontal tube 28 lead tubes which have upwardly extending portions 40 and terminate in transverse portions 4l, these latter tubes being arranged in parallel relation to each other and alternating with the tube portions 39. As shown in Figure 4, the free ends of the tube portions 41 extend through openings 42 (Figure .4) in the opposite wall of the mufile chamber to receive burners 35 as above explained.

From the above description, it will be manifest that the bottom, side and top of the central or firing zone of the mufile chamber are heated by the radiant tubes thereby creating the high temperature necessary for baking the decorated ceramic ware as it passes therethrough. This ware is gradually preheated by the tubes 25, 25, 2'! and 28 which line the side walls of that portion of the mufiie chamber between the entrance and the firing zone. The portion of the mufile chamber beyond the firing zone is of sufiicient length to enable the ceramic ware to cool down sufficiently so that after leaving the discharge end, it is substantially cool enough to be handled. Thus the length of the muffle chamber and the rate of movement of the ware passing through it are so chosen as to achieve the desired results not only from thefiring standpoint "but from the preheating and cooling.

In accordance with thi invention, the hearth of the kiln is made up of a series of transversely extending, relatively closely spaced rollers 43. The rollers are disposed slightly beneath the lower horizontal heating tubes 25 and 21 and have reduced end portions 44 which extend through apertures in the opposite side walls of the kiln. One end portion of each roller is rotatably supported in a bearing 45 carried by a bracket 46. The opposite end of each roller is carried by a bracket 41 and is similarly rotatably mounted in a bearing 48. A sprocket wheel 49 is fixed to the reduced end portion of each roller on the outer side of the supporting bracket 41. It will be understood that the series of rollers extends from one end to the other of the kiln and the sprocket wheels are conjointly driven by an endless chain 50 which in turn is engaged by a reversible drive unit 5| in the form, for example, of a reversible electric motor. The rollers are preferably of heat resisting metal such, for example, as a chrome nickel alloy.

The load such as a plurality of ceramic objects arranged, for example, in tiers, is supported on substantially rectangular bats or panels 52 which are also of metal such as chrome nickel alloy and are formed with a plurality of apertures 53 for heat transmission purposes. The bats or panels 52 are arranged in endless series and each 'bat is connected to the adjacent ones by suitable hinges 54 on one side only for a purpose which will hereinafter be described. The bats or panels 52 are of a transverse dimension slightly less than the width of the muflie chamber at its narrowest portion as indicated in Figure 3, and rest loosely upon the driven rollers 43 which provide the hearth of the kiln. Thus the frictional engagement between the bats and the rollers is relied upon to impart the translatory movement to the bats for moving them in a continuous fashion through the kiln.

At opposite ends of the kiln are curvilinear guide portions 55 of similar construction, each having a curvilinear rail 56 against which the hinged side portions of the bats or panels '52 engage, imposing a guiding influence thereon and causing the adjacent bats to spread Ian-like as they traverse the guide rail. As indicated in Figure 2, these end portions may be enclosed by metallic booths or casings 51 for assisting in retaining the heat within the mufile chamber. Joining the curvilinear end portions 55 are laterally spaced guide rails 58 which are joined by a series of rollers 59 which are closely spaced, these rollers extending from end to end of the rails 58 and also being embodied in the curved end portions 55. These rollers are mounted on suitable bearings so that they can rotate 'freely and provide a support for the chain or continuous series of bats or panels 52 during the time that they are outside of the muflle chamber.

It will be understood that by the time the decorated ceramic ware from the mufile chamber has reached the rollers on the rails 58, it-will have cooled down sufficiently to be handled without difficulty. Thus a single operator can remove the ceramic ware which has passed through the muffle chamber and also charge the bats or panels 52 with ware to be passedthrough the furnace. This involves a substantial saving in labor and enables a single operator to handle large quantities of decorated ceramic articles.

From the above description, it will be manifest that I haveproducedan exceedingly simple-and efiicient kiln which provides amufile chamber heated in a relatively inexpensive manner in such manner that satisfactory preheating is achieved as well as firing as the ware is progressed along the driven roller hearth. Thus the driven roller hearth provides a sole propelling means for the endless series or chain of bats 52. No additional drive for that portion of the chain on the outside of the kiln is necessary. By employing a reversible drive for such chain of bats, the movement of the chain can be reversed in any case found to be necessary such as jamming or breakage, etc. Another important advantage of the structure resides in the relatively small amount of space needed for the entire apparatus.

It is to be understood that numerous changes in details of construction, arrangement and operation may be efiected without departing from the spirit of the invention especially as defined in the appended claims.

What I claim is:

1. Apparatus of the class described comprising means providing a muffle chamber, heating means for said chamber, a hearth for said chamber including a series of load-supporting rollers, means to drive said rollers for progressing the load through the mufile chamber, a track on the outside of the muffle chamber and joining opposite ends thereof, an endless series of bats supported on said track and load-supporting rollers, a pivotal connection between the adjacent inside corner portions of said bats for creating a chainlike structure, and a series of idler rolls on said track for supporting said endless series of bats outside of the muffie chamber.

2. The organization as claimed in claim 1, in which the muflie chamber and track are rectilinearly elongate and curvilinear track portions join the adjacent ends of the track and chamber, there being curved guide elements to cause the bats to travel around the curvilinear track portions.

3. Apparatus of the class described, comprising means providing an elongate muflle chamber having a preheating zone, a firing zone and a cooling zone, a plurality of laterally spaced parallel radiant heating tubes extending alternately from opposite sides of the chamber and lining the top, bottom and side walls of the firing zones, means for internally heating said tubes, longitudinally extending radiant tubes joined to said first tubes and extending from the firing zone through the preheating zone, and means in the region of the entrance to the preheating zone for exhausting the gases and products of combustion from said last tubes.

4. The organization as claimed in claim 3, in which the tubes lead from the outside to the muffle chamber, and burners for projecting flames into the open ends of said tubes respectively.

5. Apparatus of the class described, comprising means providing an elongate muffle chamber having a preheating zone, a firing zone and a cooling zone, pairs of vertically spaced horizontal radiant heating tubes on opposite sides of the chamber leading from the firing zone, means adjacent the entrance of the preheating zone for exhausting the gases from said tubes, tubes extending from the outside in alternating arrangement from opposite sides to the lowermost of said horizontal tubes to afford heating of the bottom portion of the chamber, tubes extending from the outside in alternating arrangement from opposite sides to the uppermost of said horizontal tubes for heating the top portion of the chamber, and burners on the outside of the chamber for projecting flames into said last tubes respectively for radiantly heating same.

LAWRENCE L. ROOT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,663,309 Lang Mar. 20, 1928 1,738,597 Meehan Dec. 10, 1929 1,867,941 Geer July 19, 1932 1,891,469 Coleman Dec. 20, 1932 FOREIGN PATENTS Number Country Date 6,342 Great Britain 1884 379,420 France Nov. '7, 1907 

